Hormones Regulating Metabolism Flashcards
Cells in thyroid gland
- Follicular cells
- Parafollicular cells
Follicular cells
Produce T3 and T4 hormones
Follicular cell structure
Dimeric protein called thyroglobulin, modified with T3 or T4 atoms (iodine)
Function of Parafollicular cells
Produce and secrete calcitonin/thyrocalcitonin (peptide hormone)
Function of Calcitonin/thyrocalcitonin
Regulates mineral homeostasis in thyroid gland
Cells of the parathyroid gland
- Principal cells
- Oxyphil cells (unknown function)
Function of principal cells
Produce and secrete parathyroid hormone/Peptide hormone (PTH)/parathormone
Function of parathyroid hormone/Peptide hormone (PTH)/parathormone
Regulates mineral homeostasis in parathyroid gland
Adrenal gland histology
- Will see lots of lipids because gland makes lots of steroid hormones (all made of cholesterol)
- Encapsulated structure (colourless or very pale)
- Red colouration= the three zones (zona glomerulosa, zona fasiculata, zona reticularis)
- Colourless center= adrenal medulla= produces catecholamines
Adrenal gland cortex
- Steroid-secreting
- 90% of gland by weight
- Mesodermal mesenchyme
- Controlled in part by anterior pituitary
- Regulate metabolism and maintain normal electrolyte balance
- Separated into the 3 zonas: glomerulosa, fasculata, reticularis
Zona glomerulosa
Produces mineralocorticoids
Ex. aldosterone
Zona fasiculata
Produces glucocorticoids
Ex. cortisol
Zona reticularis
Produces androgens
Ex. dehydroepiandrosterone
Adrenal gland medulla
- Chromaffin cells secreting catecholamine (epinephrine and norepinephrine)
- Center of gland
- From neuroectoderm
- Richly innervated by preganglionic sympathetic fibers
Pancreatic islet endocrine cells
- Beta cells (core) release insulin (peptide hormones)
- Alpha cells (periphery) release glucagon (peptide hormones)
